Graft vs. Host Disease (GVHD) is an expensive life-threatening complication following allogeneic hematopoietic cell transplantation in some patients that receive this life-saving treatment for certain cancers. The proposed open-label, multi-center, two-part Phase 2 clinical study is designed to evaluate the potential of orBec(R), a novel formulation of oral beclomethasone 17,21- dipropionate (BDP), as a treatment for chronic gastrointestinal cGVHD. OrBec(R), as developed by Soligenix, is formulated as two separate drug products for oral administration as an immediate release and delayed release tablet, each containing 1 mg of BDP, a potent, locally-acting corticosteroid originally developed primarily for the prevention and treatment of acute gastrointestinal graft versus host disease (aGVHD). The reduced systemic bioavailability of oral BDP offers a major therapeutic advantage over systemic glucocorticoids such as prednisone and methylprednisolone, which have well-recognized adverse effects (e.g., development of glucose intolerance, Cushingoid habitus, muscle weakness and fatigue, bone demineralization, and increased risks of infections). Adverse effects of systemic glucocorticoid administration can be avoided by use of topically active glucocorticoids. The protocol for this Phase 2 CLINICAL STUDY was submitted to IND 20,212 June 24, 2011. To date, no additional FDA feedback on the study design has been noted by the FDA. We will conduct this Phase 2 clinical study with the following specific goals, which form the Specific Aims of this proposal: To conduct a FDA reviewed and accepted Phase 2 clinical study: the study will be a point estimate design aimed at elucidating the dose response needed to define future placebo-controlled studies. The placebo-controlled study will be the Phase 3 clinical study that will be described in the Phase II SBIR proposal. This study will estimate the proportion of subjects who achieve a complete response (CR), partial response (PR) and overall response (OR) of GI GVHD signs and symptoms when treated with orBec(R), 2 mg four times a day (8 mg/day) for up to 16 weeks, in patients with cGVHD. The secondary objectives of this study are to determine the: i. proportion of subjects who experience a flare/worsening of GI GVHD; ii. time to flare/worsening of GI GVHD at each dose-level; iii. time to CR during the initial 16 weeks of orBec(R) treatment; and iv. time to flare/worsening of GI GVHD signs and symptoms during each of the planned orBec(R) dose reductions in Part 2 of the study. The safety objectives are to evaluate safety and tolerability of orBec(R) in subjects with cGVHD. Upon completion of the Phase 2 clinical study, Soligenix will be in a position to begin the process for a Phase 3 FDA reviewed and accepted clinical study, on the road to the first drug to be approved for treatment for cGVHD.